Absolutely everything has more complexity than is visible on the surface. Just go in with that assumption and you wont make yourself look like a fool. I also often find you only really look like a fool when you confidently make incorrect statements and denigrate others. Making incorrect statements / assumptions with the openness to learn from a small horse instead of a high horse is admirable not foolish.
Ah, isn't it more fun to just gleefully embrace your ignorance and arrogance? Come up with a back of the napkin solution and throw it out there. The professional will probably enjoy the opportunity to show off by picking it apart, right?
